interface DemoState {
    count: number;
  }
  const state: DemoState = {
    count: 0
  };
  export default {
    state,
    mutations: {
      increase(state: DemoState) {
        console.log(state);
        state.count++;
      },
      decrease(state: DemoState) {
        console.log(state);
        state.count--;
      }
    }
  };